AND, I did some re-thinking. My pee issues were multi faceted. Stress was a factor, marking for territorial control was, too. I also noticed some secret stalking like behaviour in which one cat, Ari, would lay across a threshhold blocking two litterboxes in two separate rooms. Score points for ingenuity, lose points for sucessful pee blocking tactics. I now have one box more on this main level, and I think I outsmarted Ari. I *think*!!
I havent found pee but a couple times in the last 30 days and none in the last week.